The radial head transmits forces from the wrist to the elbow and serves as a central stabilizer of the lateral joint guidance. In displaced or complex radial head fractures, the stability of the entire elbow joint may be compromised. Modern radial head prostheses are anatomically shaped and designed to replicate natural structures, helping to restore these biomechanical functions.
The elbow joint consists of three interconnected sub-joints that function together. The radial head is part of this complex joint mechanism, enabling coordinated movement between the radius, ulna, and humerus. In cases of elbow injuries, joint stability is often impaired. A correctly positioned radial head prosthesis restores the physiological rotation of the forearm and stabilizes the lateral ligament complex.
Radial Head Prostheses in Modern Trauma Surgery
Radial head fractures account for approximately one-third of all elbow injuries. Especially in displaced or comminuted radial head fractures, surgical treatment is necessary to restore elbow joint stability. The therapy depends on the severity of the injury as well as on anatomical and biomechanical factors. In reconstructable fractures, open reduction and osteosynthesis may be performed.
When the fracture is complex or severely comminuted, primary implantation of a radial head prosthesis is recommended. This replaces the head of the radius with an anatomically shaped implant that stabilizes mobility and preserves joint kinematics. Associated injuries to ligaments or the capitulum can be surgically repaired at the same time. Implantation of radial head prostheses is performed via a lateral approach to the elbow and follows the principles described by Morrey and Van Riet RP.
The prosthesis stabilizes the radial head and preserves elbow function. Studies published in the J Shoulder Elbow Surg, J Bone Joint Surg Br, and Clin Orthop Relat Res confirm that radial head prosthesis after radial head fracture achieves excellent clinical outcomes.
In non-reconstructable fractures, the damaged radial head is removed and replaced with an anatomically fitted radial head prosthesis. This procedure aims to restore elbow joint function and stability. The prosthesis is implanted via a lateral approach, with the stem anchored within the radius.
Implantation of a radial head prosthesis stabilizes the joint structure and helps prevent secondary complications such as osteoarthritis or instability. Modern implants—including monopolar and bipolar radial head arthroplasty systems—allow precise adaptation to individual anatomy. Comparative studies in the J Hand Surg, J Orthop Trauma, and Ulster Med J report high success rates with a mean follow-up of several years.
Compared to radial head resection or other prosthetic designs, this method offers clear advantages in terms of functional stability and postoperative rehabilitation. Radial head resection is now rarely performed, as it increases the risk of joint instability. Modern systems, such as the Tornier prosthesis, provide long-term joint stability and improve the overall prognosis.
Illustration of a radial head prosthesis in a radial head fracture: the prosthesis replaces the damaged radial head and stabilizes the elbow joint.
Reconstruction or Resection of the Radial Head – When Is a Prosthesis Necessary?
Radial head resection is used only in rare cases when implantation of a radial head prosthesis is not feasible. While resection can temporarily relieve pain, it often leads to long-term elbow instability. In contrast, an anatomically adapted radial head prosthesis provides lasting joint stability and preserves natural kinematics. Studies in the J Shoulder Elbow Surg and J Orthop Trauma show that radial head resection results in higher complication and functional loss rates compared to prosthetic implantation.
The Mason classification categorizes radial head fractures into different severity levels. In particular, Mason type III fractures—displaced and multifragmentary—require surgical intervention. While reconstructable fractures can be managed with osteosynthesis, in complex cases, a radial head prosthesis for non-reconstructable fractures is the preferred treatment option. Factors such as associated injuries, instability, and the condition of the radial head determine whether reconstruction, resection, or prosthetic implantation is indicated.
Prosthetic Designs and Materials for Radial Head Arthroplasty
Various prosthetic models are used for radial head arthroplasty. Monopolar systems feature a fixed connection between the head and stem, while bipolar radial head arthroplasty allows a mobile head that better adapts to joint kinematics. Modular implants enable individual adjustment to the patient’s anatomy and improve elbow joint stability. These systems are the standard in modern trauma surgery, as they optimally meet biomechanical requirements and support natural elbow motion.
Numerous clinical studies, including those published in the J Bone Joint Surg Br, Clin Orthop Relat Res, and J Am Acad Orthop Surg, demonstrate favorable functional results following radial head prosthesis implantation. Biomechanical analyses confirm that modern implants stabilize load distribution within the joint and maintain full range of motion. Outcomes after bipolar radial head arthroplasty or modular implantation are long-term stable, showing high patient satisfaction and low revision rates.
Postoperative rehabilitation typically begins shortly after surgery, often within a few days. Targeted physical therapy helps restore joint function and reduces the risk of motion restriction. Structured rehabilitation and physiotherapeutic care promote healing and help prevent complications such as osteoarthritis or instability. The gradual increase in elbow loading plays a central role in achieving full range of motion recovery.
Rehabilitation usually starts within a few days after radial head prosthesis implantation. The goal is to gradually restore elbow mobility and stabilize the implant. Postoperative protocols follow standardized regimens based on current evidence and expert recommendations, including those from Van Glabbeek F and Morrey.
Early mobilization is crucial in treating radial head fractures to prevent complications. After radial head replacement for acute fractures, gradual loading can begin within a short time. Modern prosthetic systems such as Tornier implants support stable healing and reduce risk factors for revision surgery.
Functional rehabilitation is often carried out in specialized orthopedic and trauma centers. It includes physiotherapy aimed at promoting joint motion and rebuilding muscle strength. Studies such as “The radius with a review of treatment of comminuted fractures of the radial head” and “A cadaver study for radial head stability” confirm that structured rehabilitation is essential for optimal functional outcomes.
After approximately six to eight weeks, the joint is generally weight-bearing, and most patients regain good mobility. Follow-up evaluations typically occur after radial head implantation with a mean follow-up of several months to assess joint function and stability.
Despite the high success rate, certain complications can occur following radial head prosthesis implantation. In rare cases, infection, implant loosening, or limited range of motion may develop. Studies in J Shoulder Elbow Surg, J Hand Surg, and J Orthop Trauma report that complications are more common in unstable or multiply displaced radial head fractures.
Improper implant positioning or poor anatomical fit may lead to biomechanical problems. Therefore, precise alignment and proper placement at the capitulum are essential to ensure optimal elbow joint stability. Modern monopolar and bipolar radial head systems significantly reduce this risk.
Other potential risks include early osteoarthritis or associated injuries that may delay healing. In rare cases, revision surgery may be required. However, studies from Clin Orthop Relat Res and J Bone Joint Surg Br demonstrate that most patients achieve long-term stability and that the prosthesis continues to provide durable elbow joint function.
When is a radial head prosthesis necessary?
A radial head prosthesis is indicated when the radial head is destroyed by a complex fracture—typically Mason type III—and reconstruction is no longer feasible. Implantation restores joint stability and helps prevent instability or osteoarthritis.
How is the surgery performed?
The procedure begins with removal of the damaged radial head, followed by precise positioning of the implant within the elbow. The surgery stabilizes the joint and allows for early postoperative rehabilitation.
What are the potential risks of implantation?
Possible risks include infection, implant loosening, or temporary motion restriction. However, serious complications are rare thanks to modern implant systems such as Tornier and Morrey designs.
How long does postoperative rehabilitation take?
Rehabilitation typically lasts six to eight weeks. During this time, elbow mobility is gradually increased to restore full range of motion. Targeted physiotherapy enhances joint function and reduces the risk of instability.
What are the long-term outcomes?
Long-term studies with a mean follow-up of several years show that patients achieve excellent stability and mobility after radial head prosthesis implantation. In most cases, the joint remains durable and the prosthesis maintains optimal elbow biomechanics.
